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The latest trends in the use and composition of dental prostheses have been reviewed, and 66 patients referred by dermatologists and odontologists patch tested. The allergen series used were: TRUE Test standard series; Chemotechnique dental screening series; specially prepared metals series. The allergens found to be positive, in order of frequency, were: nickel, cobalt, potassium dichromate, rhodium, palladium, mercury, beryllium, methyl methacrylate, copper and zinc.

There are various references to sensitization to beryllium in the literature. Since introducing a patch testing series for patients with suspected sensitization to metals, we have found 3 cases of sensitization to beryllium. Of these 3 cases, we regard the first 2 as having relevant sensitization. Beryllium chloride (1% pet.) was positive in 3 patients and negative in 150 controls.

Cocoamidopropylbetaines are surfactants frequently used in cosmetics. We have evaluated the irritant capacity of 3 different qualities of cocoamidopropylbetaine, using the following method: patch tests have been carried out with 5 different dilutions in 67 patients and the results read at 2 days by noninvasive methods (direct visualization, transepidermal water loss (TEWL), laser Doppler flowmetry (LDF)). The results with the 3 methods were concordant. However, the results with the different concentrations were paradoxical, as irritancy did not increase at higher concentrations. We have tried to explain this by the fact that these substances contain by-products (free amidoamine and sodium monochloroacetate), the concentrations tested all being above the critical micelle concentration and therefore containing both micelles and monomer. Finally, we believe that noninvasive methods such as TEWL and LDF could be of great use in the evaluation of irritant contact dermatitis.

Owing, on the one hand, to the constant increase in the %s of nickel sensitization in the majority of allergy departments of dermatology and, on the other, to the fact that sensitization to nickel is almost always through contact with jewellery and imitation jewellery, an update was carried out on the metal alloys principally used in the manufacture of such jewellery (earrings, bracelets, necklaces, rings, watch straps, etc.) The conclusions of this review demonstrate that nickel is irreplaceable in the majority of the alloys, because of its excellent technical properties and low price and, as a result, the % of sensitizations to this allergen will not only maintain their present high level but will probably increase in the future.

Clenbuterol, a beta antagonist, and ranitidine, a histamine-receptor antagonist, were associated with contact dermatitis in a chemist. The allergen in the former was an intermediate in the synthesis called beta. In the latter, intermediates and the finished base and hydrochloride were responsible.

Firstly we showed the reason for the choice of each product used in the preparation of this cosmetic. After this we studied "in vitro" the effect of this preparation, and "in vivo" in 25 patients sensitive to Potassium dichromate. On seeing the null effect of this preparation, owing to the oxidation of ascorbic acid, on these 25 patients, we modified the formula, substituting the ascorbic acid and EDTA, respectively, for tartaric acid and glycine. The respective tests "in vitro" and "in vivo" on 20 patients, this time showed beneficial effect of this preparation in 60% of the patients tested. Of these 60%, a 25% have continue to work exposed to the allergen (dichromate or nickel) and the other 35% have continue working with lesions controlled by habitual topic therapy. This preparation can also be used, with less effect, for nickel.

A case of contract sensitization to the ethylene oxide by a mask sterilized with this substance is reported. The mask was correctly sterilized but the ethylene oxide was not completely evaporised. The path tests were positive in the patient but negative in 25 control subjects. The patch tests with the international series and with all the elements of the mask were negative. The possible troubles of ethylene oxide and the sterylisation methodes of this substance are reviewed.

230 patients with occupational dermatitis in the metallurgic industry were studied with standard patch test (GEIDC) and an oil series. An occupational and clinical questionnaire survey was carried out. Responses to paraphenylenediamine, chrome, cobalt in the standard series, and benzisothiazolone, triethanolamine, and Grotan BK were the main positive results.

The results of the study of 51 patients bearing a Milwaukee corset indicate that they present a mechanical and irritative dermatitis caused by the personal predisposition, the action of the plastic material and the occlusion and humidity produced between skin surface and the corset. The authors suggest the name Occlusive Dermatitis Syndrom for this cases as a subtype of Mechanical Irritative Dermatitis.

A man affected of a femur osteomyelitis was treated with Septopal (Merck) and presented an allergic contact dermatitis on the left thigh, thorax, abdomen with bilateral oedema of eyelids and generalized pruritus. The cause was a co-polymer of methyl-methacrylate-methacrylate of the material of the small balls of Septopal, which liberates gentamycin contained inside through little pores.

There are three types of hand dermatitis in housewives. The most usual are cured when housework is stopped. Another type is that of housewife contact dermatitis which appears on pre-existing endogenous lesions such as dyshidrosis or nummular eczema. The third form is housewife hand contact dermatitis which appears, or coexists with, localized endogenous lesions of the hands. The last two forms are not cured when housework is stopped. In some cases the three forms may coexist or appear one after another. It is not usual for a person suffering from typical flexural atopic dermatitis to present with one of the described three forms of hand dermatitis. Nevertheless, without having some relationship to atopic diathesis no woman could suffer from any of these three forms of dermatitis. In spite of the lack of analytical data, everyday clinical facts (one example being these different forms of housewife hand dermatitis) suggest the need to accept a subgroup of cutaneous atopic diathesis.

An hitherto undescribed type of contact dermatitis in a series of 16 patients is described by the authors. The lesions were localized in the anterior and anterolateral aspects of the thighs and were sharply limited in the area contacting the trouser pockets, manufactured with synthetic fabrics. In 17 patients of this series there was a concomitant dermatitis in the exposed areas of the face and hands. The authors described the processing in the manufacture of these pockets, the end step being the obtention of poliamide, through different precursor substances. The poliamide is treated with different aditives giving rise to the nylon fiber, which is used to manufacture the definitive tissue. A list of adequate allergens and their concentrations used in the 16 patients is given in the paper. The results of the patch tests and the fact that all the clinical symptoms of the patients disappeared after the withdrawal of the tissue pockets and substitution by cotton tissue give a reasonable basis to the hypothesis of contact dermatitis caused by this tissue. However, the true specific allergen is not demonstrated yet.

Among 4600 patients tested in 5 years (1973--77), 5.02% of them (231 cases) presented positivity to Benzidine. Of them 16.4% (38 cases) showed concomitant sensitization to one or more allergens of the tested substances of p-amino compounds group. Among the patients who suffered from clinically diagnosed occupational contact dermatitis and showed a positive reaction to Benzidine, 66% of them showed positive reactions to Benzidine as a unique patch-test positivity, whereas 34% of them reacted to Benzidine and to other allergens as well. The occupations where a sensitization to other allergens as well. The occupations were a sensitization to Benzidine was found in a relatively high number were: mechanical industry, house-wives, construction workers, textile industry, hairdressers, and chemical industry. Histological studies of the patch-tests confirm the allergic nature of the reaction. The sources of eventual sensitization and the significance of the circumstantial positivities to this allergen are discussed.